Pen point



C. PFANSTIEHL PEN POINT Original Filed Jan. 13, 1934 V Sept. 8, 1936.

I 0 WM 1e I v .1////\ K g i w 5 2 5 %m a w w Patented Sept. 8, 1936 PATENT OFFICE PEN rom'r Carl Pfanstiehl,

Waukegan. Ill., minor to Pfanstiehl Chemical 00., a corporation of Illinois Original application January 13, 1934, Serial No.

Divided and this application Septembe! 1, 1934, Serial No. 742,493

3 Glaims.

This invention relates to pen-points and a method of preparing the same, and particularly to pen-points in which the tip and nib are integral.

5 In my co-pending application Serial No. 706,565, filed January 13, 1934, now Patent No. 2,005,752, issued June 25, 1935 of which this application is a division, is described a process of tacking and welding tips to pen nibs, and a method of forming integral tips upon pen-nib material. I

The present invention is illustrated in the drawing,'in which Fig. 1 represents an integrally formed pen-point having two spherical tips;

Fig.2 represents an integral pen-point having one spherical tip; Fig. 3 is a broken elevation, partly in section, of the fusing apparatus: Fig. 4 is an elevation of the pen-point holder, partly in section, and Fig. 5 is the side elevation showing the relation of the pen-point to the arc.

' In carrying out the operation a pen-nib i0 is grasped in the jaws H. The jaws are part of a copper holder i3 which is provided with a collar 26. After placing a pen nib in the jaws i2 it is placed within the fusing apparatus shown in Fig. 3. This apparatus comprises a tungsten filament 219, centrally located near the bottom of a Pyrex glass enclosed chamber 30, set in rubber gaskets Mi.- A hose 3! having outlets 32 is provided below the filament for the admission of a gentle stream of hydrogen or other readily ionizable gas. Hydrogen is preferred because of its tendency to prevent the formation of a metallic arc and because it provides areduc ing atmosphere. The base of chamber 80 is divided by insulation ll into portions 33 and 34. Filament 29 is set in copper terminals 35 and 36, which are electrically connected to a welding circuit which is more fully described in my co-pending application Ser. No. 706,565. A

copper cover 31 is provided at the top of chamber 30, and is supplied with a central'aperture l2 for the nib and holder to pass through. This opening is preferably substantially closed by the 46 holder. but sufficient space is left for the gasesto escape. Rising from the cover 31 is the neck 38, provided with copper cooling fins 39. Other cooling means may of course be substitued, for example, water cooling means. The collar 26 50 of the holder l3 seats itself upon the shoulders 43 of the neck 38, and therebyestablishes the proper distance between the tip II and the filament 29.

As shown in Fig. 4. the nib is held by the.

jaws I! a very short distance from the tip. Generally this distance will be from to 01 an inch or less, but the distance depends upon the thickness of the nib andother factors which will be obvious to one skilled in the art. The cooling effect of the jaws plus the connected 5 cooling means on the neck is sufiicient to prevent any of the nib except that exposed from fusing, or even reaching a temperature which will draw the temper from the nib. The duration of the arc is preferably timed so that it 10 will not continue unduly after formation of a spherical globule upon the tip of the nib.

Fig. 5 shows a preferred setting of the filament, although other arrangements may be used if desired. lb

The tungsten filament is continuously heated.

The are circuit comprises a 220 or volt A. C. supply which is stepped up by a transformer to 800-1000 volts. The tungsten filament is continuously heated by a high amperage low 20 voltage current, for example, 30 amperes and 1 volts. The operation of the are is controlled by v a'timing switch which may be set to cause an arc of any desired duration. With a hot tungsten filament and an ionized atmosphere of hydrogen 5 and a gap of about ya" between the hot filament and the pen nib, a time of the order of l-2 seconds is satisfactory.

The hot filament ionizes the hydrogen and thereby greatly lowers the resistance of the gap 30 so that only 800-1000 volts are necessary to start the arc with hydrogen.

I In carrying out the tip-forming operation, the

pen-nib which has been placed in the jaws l2 of the holder i3 with the tip of the nib exposed only 35 about or less beyond the end of the jaws is placed within the fusing apparatus shown in Fig. 3. In the meantime the tungsten filament current has been started so that the filament is hot and a stream of hydrogen is passed gently 40 through the chamber 30 and ionizes as it passes the filament. The stream should be sufiiciently slow so that the atmosphere in the chamber is substantially quiescent. The timing switch is then started. The operation of the arc heats the 45 pen nib .by heat received substantially entirely from below and the jaws of the holder l3 act as conductors to cool the remaining portions of the nib so that they do not fuse, nor is the temper thereof lost. For example, with a steel pen a 50 substantially perfect sphere or globule of steel may be formed on the end of the pen, which may be readily split in the usual way. Substantially no bumng is required, but a perfectly smooth writin p int is obtained.

Likewise an ordinary steel pen-nib may be formed to shape and split but the end not polished for writing. It may then be placed in the welding apparatus with the two points of the nib separated a few thousandths of an inch and exposed to the arc in the usual manner, except that the time and maximum current should be cut down considerably. In this manner a. rounded surface of glassy smoothness is produced on each separate point of the pen.

When an air-hardening steel is used for the nib, the sudden heating and cooling produces the maximum hardness at the tip of the pen. For this purpose the use of a hydrogen atmosphere is beneficial in view of the fact that it conducts heat away much more rapidly than air.

Fig. 1 shows a steel pen ll) treated with its point split to produce a spheroidal globule ll upon each tip. The treatment may be carried so far as to produce a substantially spherical globule, or it may be stopped somewhat short of this when the tip is simply rounded or smoothed, in a somewhat similar fashion to the manner in which a rough piece of glass may be smoothed by heat. In either event, with a properly hardening steel, the tip itself is hardened to a degree which is not possible to the entire pen."

The process may be used with other types of metallic pen-point material to produce spherical tips.

In Fig. 2 is shown a point I with an integral single tip I I which may be split in the customary manner.

The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitations should be understood therefrom, but the appended claims should be construed as broadly as permissible, in view of the 10 prior art.

What I claim as new and desire to secure by Letters Patent is:

1. An integral steel pen nib comprising a body portion having a steel tip integral with the body portion and terminating in at least one spheroid of the steel formed by fusion.

2. An integral steel pen nib comprising a body portion having a steel tip integral with the body portion and terminating in at least one spheroid of the steel formed by fusion, the metal of which is substantially harder and substantially less flexible than the body portion.

3. A pen nib as set forth in claim 1 in which the tip is splitand each point thereof is provided with a spherold.

CARL PFANS'IIEI-ll... 

